Browse Prior Art Database

Signal Transmission and Reconstruction System

IP.com Disclosure Number: IPCOM000094062D
Original Publication Date: 1966-May-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 3 page(s) / 76K

Publishing Venue

IBM

Related People

Dorrell, CE: AUTHOR [+3]

Abstract

The system produces at a central location an oscilloscope trace being observed at a remote location. The system provides a diagnostic tool for the solution of electronic data processor error conditions.

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Signal Transmission and Reconstruction System

The system produces at a central location an oscilloscope trace being observed at a remote location. The system provides a diagnostic tool for the solution of electronic data processor error conditions.

The remote transmitter is shown in A. Oscilloscope 1 is the source of waveform information and forms the input to A-to-D converter 2. The outputs of A-to-D2 are ordered pairs of significant coordinates for insertion in delay line buffer TB 3. When a description of a complete line of a signal trace is stored in TB 3, data transmitter T 4 is signalled. T handles the line coordination and transmission of the signal to the other end via acoustical coupler C 5 which attaches to a telephone handset.

At the receiving portion, the signal is recovered from the line in acoustic decoupler D 6. A data receiver R 7 recovers synchronization and message format, depacks the data, and loads Line image into a receiving delay line buffer RB8. From RB8, the image can be displayed in another scope 9 via a D-to-A converter 10. An alternate buffer AB 11 can be used to save a signal for comparison. Since only significant coordinate pairs are transmitted, with unpacking done at the receiving terminal, the actual transmission time on the telephone line is greatly reduced.

The circuitry of A-to-D 2 is shown in B. The X axis sample pulse generator of scope 1 puts out one pulse per sweep of the ramp input. The feedback to the differential input on line 12 causes the pulse to occur at a higher point on the ramp. This pulse drives X counter 13 to provide the X address. Each time an X sample occurs, the output of the A-to-D converter 14 is sampled into register 15. This sample is compared to the last value of Y temporarily held in hold register 16 in compare unit 17. If the compare operation is equal, the current sample is redundant and as such is discarded. Another sample is taken on the next sweep. When an unequal sample is taken, sampling is suspended until the sample is loaded into TB 3. At this time the new Y value is stored in 16. Thus waveform description is obtained by ordered pairs. Specifically, the X address indicates the starting point of a certain Y value. No more order pairs are transmitted until the Y value changes. Automatically, the intervening...